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1.
Int J Sports Physiol Perform ; 15(9): 1231-1236, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32084627

RESUMO

The purpose of this research was to evaluate the performances of female middle- and long-distance runners before and after the implementation of a new antidoping strategy (the Athlete Biological Passport [ABP]) in a country accused of systematic doping. A retrospective analysis of the results of Russian National Championships from 2008 to 2017 was performed. The 8 best female performances for the 800-m, 1500-m, 3000-m steeplechase, 5000-m, and 10,000-m events from the semifinals and finals were analyzed. The yearly number of athletes fulfilling standard qualifications for international competitions was also evaluated. Overall, numbers of athletes banned for doping in 2008-2017 were calculated. As a result, 4 events (800, 1500, 5000 [all P < .001], and 10,000 m [P < .01]) out of 5 showed statistically significant deterioration in the performances when comparing before and after the introduction of the ABP. The 3000-m steeplechase was the only event that did not show statistically significant change. The highest relative decrease in the number of runners who met standard qualification for international competition was for the 5000-m event (46%), followed by 1500-m (42%), 800-m (38%), 10,000-m (17%), and 3000-m steeplechase (1%). In conclusion, implementation of the ABP was followed by a significant reduction in the performance of female runners in a country accused of systematic doping. It can be reasonably speculated that more stringent antidoping testing, more specifically the introduction of the ABP, is a key reason for this reduction.

2.
Int J Sports Physiol Perform ; 13(8): 1090-1096, 2018 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-29431548

RESUMO

PURPOSE: The authors investigated the effects of sex, energy availability (EA), and health status on the change in hemoglobin mass (ΔHbmass) in elite endurance athletes over ∼3-4 wk of live-high-train-high altitude training in Flagstaff, AZ (2135 m; n = 27 women; n = 21 men; 27% 2016 Olympians). METHODS: Precamp and postcamp Hbmass (optimized carbon monoxide rebreathing method) and iron status were measured, EA was estimated via food and training logs, and a Low Energy Availability in Females Questionnaire (LEAFQ) and a general injury/illness questionnaire were completed. Hypoxic exposure (h) was calculated with low (<500 h), moderate (500-600 h), and high (>600 h) groupings. RESULTS: Absolute and relative percentage ΔHbmass was significantly greater in women (6.2% [4.0%], P < .001) than men (3.2% [3.3%], P = .008). %ΔHbmass showed a dose-response with hypoxic exposure (3.1% [3.8%] vs 4.9% [3.8%] vs 6.8% [3.7%], P = .013). Hbmasspre was significantly higher in eumenorrheic vs amenorrheic women (12.2 [1.0] vs 11.3 [0.5] g/kg, P = .004). Although statistically underpowered, %ΔHbmass was significantly less in sick (n = 4, -0.5% [0.4%]) vs healthy (n = 44, 5.4% [3.8%], P < .001) athletes. There were no significant correlations between self-reported iron intake, sex hormones, or EA on Hbmass outcomes. However, there was a trend for a negative correlation between LEAFQ score and %ΔHbmass (r = -.353, P = .07). CONCLUSIONS: The findings confirm the importance of baseline Hbmass and exposure to hypoxia on increases in Hbmass during altitude training, while emphasizing the importance of athlete health and indices of EA on an optimal baseline Hbmass and hematological response to hypoxia.


Assuntos
Altitude , Desempenho Atlético/fisiologia , Hemoglobinas/análise , Hipóxia , Condicionamento Físico Humano/métodos , Adulto , Atletas , Dieta , Metabolismo Energético , Feminino , Humanos , Estudos Longitudinais , Masculino , Adulto Jovem
3.
Int J Sport Nutr Exerc Metab ; 28(4): 403-411, 2018 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-29252050

RESUMO

We aimed to (a) report energy availability (EA), metabolic/reproductive function, bone mineral density, and injury/illness rates in national/world-class female and male distance athletes and (b) investigate the robustness of various diagnostic criteria from the Female Athlete Triad (Triad), Low Energy Availability in Females Questionnaire, and relative energy deficiency in sport (RED-S) tools to identify risks associated with low EA. Athletes were distinguished according to benchmarks of reproductive function (amenorrheic [n = 13] vs. eumenorrheic [n = 22], low [lowest quartile of reference range; n = 10] versus normal testosterone [n = 14]), and EA calculated from 7-day food and training diaries (< or >30 kcal·kg-1 fat-free mass·day-1). Sex hormones (p < .001), triiodothyronine (p < .05), and bone mineral density (females, p < .05) were significantly lower in amenorrheic (37%) and low testosterone (40%; 15.1 ± 3.0 nmol/L) athletes, and bone injuries were ∼4.5-fold more prevalent in amenorrheic (effect size = 0.85, large) and low testosterone (effect size = 0.52, moderate) groups compared with others. Categorization of females and males using Triad or RED-S tools revealed that higher risk groups had significantly lower triiodothyronine (female and male Triad and RED-S: p < .05) and higher number of all-time fractures (male Triad: p < .001; male RED-S and female Triad: p < .01) as well as nonsignificant but markedly (up to 10-fold) higher number of training days lost to bone injuries during the preceding year. Based on the cross-sectional analysis, current reproductive function (questionnaires/blood hormone concentrations) appears to provide a more objective and accurate marker of optimal energy for health than the more error-prone and time-consuming dietary and training estimation of EA. This study also offers novel findings that athlete health is associated with EA indices.


Assuntos
Traumatismos em Atletas/fisiopatologia , Densidade Óssea , Osso e Ossos/lesões , Ingestão de Energia , Metabolismo Energético , Desnutrição/fisiopatologia , Adulto , Amenorreia/fisiopatologia , Atletas , Estudos Transversais , Feminino , Síndrome da Tríade da Mulher Atleta , Humanos , Masculino , Necessidades Nutricionais , Fenômenos Fisiológicos da Nutrição Esportiva , Inquéritos e Questionários , Testosterona/sangue , Tri-Iodotironina/sangue , Adulto Jovem
4.
Am J Physiol Heart Circ Physiol ; 286(5): H1821-6, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-14726297

RESUMO

We studied the effect of regular physical activity on cardiac and vascular autonomic modulation during a 5-yr controlled randomized training intervention in a representative sample of older Finnish men. Heart rate variability (HRV) and blood pressure variability (BPV) are markers of cardiac and vascular health, reflecting cardiac and vascular autonomic modulation. One hundred and forty randomly selected 53- to 63-yr-old men were randomized into two identical groups: an intervention (EX) group and a reference (CO) group, of which 89 men remained until the final analysis (EX: n = 47; CO: n = 42). The EX group trained for 30-60 min three to five times a week with an intensity of 40-60% of maximal oxygen consumption. The mean weekly energy expenditure of the training program for the 5-yr training period was 3.80 MJ, and 71% of the EX group exceeded the mean. The EX group had a significantly (P < 0.01) higher oxygen consumption at ventilatory aerobic threshold (VO2VT) than the CO group at the 5-yr time point. VO2VT had a tendency to increase in the EX group and decrease in the CO group (interaction P < 0.001) from the baseline to the 5-yr time point. Peak performance did not change. Low-frequency power of R-R interval variability decreased in the EX group (P < 0.01, by 6%) from the baseline to the 5-yr time point. BPV did not change. In conclusion, low-intensity regular exercise training did not prevent HRV from decreasing or change BPV in 5 yr in older Finnish men.


Assuntos
Pressão Sanguínea , Frequência Cardíaca , Educação Física e Treinamento , Antropometria , Metabolismo Energético , Coração/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Consumo de Oxigênio , Fenômenos Fisiológicos Respiratórios
5.
Clin Physiol Funct Imaging ; 22(3): 173-9, 2002 May.
Artigo em Inglês | MEDLINE | ID: mdl-12076342

RESUMO

PURPOSE: To study the influences of a 1-year controlled, randomized endurance exercise training period on heart rate (HR) and blood pressure variability in a representative sample of Finnish men in their late middle age. METHODS AND RESULTS: Subjects were 140 sedentary men aged 53-63 years. The men were randomized into two identical groups: an intervention (EX) and a reference (CO) group. One hundred and twelve of them remained in the final analysis (EX: n=59, CO: n=53). EX trained for 30-60 min three to five times a week with the intensity of 40-60% of maximal oxygen consumption. In EX, 1 year of regular exercise training increased oxygen consumption at respiratory compensation threshold by 11% (P < or = 0.001) in a maximal cardiorespiratory test. Total power and very low frequency power of R-R interval variability (ms2) tended to increase in the EX group by 26 and 42% and to decrease in the CO group by 13 and 10% (interaction P<0.05 and P<0.01), respectively. There were no significant changes in blood pressure variability. CONCLUSION: Regular low- to moderate-intensity exercise training could retard the declining tendency in cardiac autonomic nervous function in older men during 1 year.


Assuntos
Pressão Sanguínea/fisiologia , Frequência Cardíaca/fisiologia , Resistência Física/fisiologia , Sistema Nervoso Autônomo/fisiologia , Composição Corporal , Humanos , Estilo de Vida , Masculino , Pessoa de Meia-Idade , Consumo de Oxigênio/fisiologia , Descanso , Decúbito Dorsal
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